Nokia India — service centre

I am complaining about the nokia service centre as they promised me to repair my phone by the given time period but they told me that they called me to approve the startup for the repair process, but i didn't recieved any call from them and now they are saying that the process will take more days than they told me to repair it. And also they didn't order the required part for the device that i told them to order as soon as possible. I didn't expect this from nokia india. (Sai solutions nokia, south extension, new delhi)